SYDNEY, Australia (AP)  An obesity pandemic threatens to overwhelm health systems around the globe with illnesses such as diabetes and heart disease, experts at an international conference warned Sunday.

"This insidious, creeping pandemic of obesity is now engulfing the entire world," Paul Zimmet, chairman of the meeting of more than 2,500 experts and health officials, said in a speech opening the weeklong International Congress on Obesity. "It's as big a threat as global warming and bird flu."

The World Health Organization says more than 1 billion adults are overweight and 300 million of them are obese, putting them at much higher risk of diabetes, heart problems, high blood pressure, stroke and some forms of cancer.

Zimmet, a diabetes expert at Australia's Monash University, said there are now more overweight people in the world than the undernourished, who number about 600 million.

People in wealthy countries lead in overeating and not doing enough physical activity, but those in the poorer nations of Asia, Africa and Latin America are quickly learning bad habits, experts said.

Thailand's Public Health Ministry, for instance, announced Sunday that nearly one in three Thais over age 35 is at risk of obesity-related diseases.

"We are not dealing with a scientific or medical problem. We're dealing with an enormous economic problem that, it is already accepted, is going to overwhelm every medical system in the world," said Dr. Philip James, the British chairman of the International Obesity Task Force.

The task force is a section of the International Association for the Study of Obesity, a professional organization of scientists and health workers in some 50 countries that deal with the issue.

James said the cost of treating obesity-related health problems was immeasurable on a global scale, but the group estimated it at billions of dollars a year in countries such as Australia, Britain and the United States.

Among the most worrying problems are skyrocketing rates of obesity among children, which make them much more prone to chronic diseases as they grow older and could shave years off their lives, experts said.

The children in this generation may be the first in history to die before their parents because of health problems related to weight, Kate Steinbeck, an expert in children's health at Sydney's Royal Prince Alfred Hospital, said in a statement.

Experts at the conference said governments should impose bans on junk food advertising aimed directly at children, although they acknowledged such restrictions were unlikely to come about soon because the food industry would lobby hard against them.

"There is going to be a political bun fight over this for some time, but of course we shouldn't advertise junk food to children that makes them fat," said Dr. Boyd Swinburn, a member of the International Obesity Task Force.

Dr. Claude Bouchard, president of the International Association for the Study of Obesity, an umbrella group for medical organizations dealing with weight-related and children's health issues, said the group supported advertising bans as official policy.

But the policy position is unlikely to have any immediate effect on influencing governments to introduce such bans, said Bouchard, head of the Pennington Research Center at Louisiana State University at Baton Rouge.

Copyright 2006 The Associated Press. All rights reserved. This
material may not be published, broadcast, rewritten or redistributed.